Fig 1: Dependence on HCK for DPP8/9 inhibitor-induced pyroptosis. (A) Expression level of DPP8, DPP9, caspase-1, CARD8, GSDMD, or caspase-3 in THP-1, MM.1S, KARPAS299, KG1, NAMALWA, or Daudi cells was estimated by Western blot analysis. (B) Gene expression of THP-1, MM.1S, KARPAS299, KG1, NAMALWA, or Daudi cells was analyzed by microarray method using 3D-Gene. (C) Expression level of HCK, LCK, Fyn, c-Fgr, Lyn, or Blk in THP-1, MM.1S, KARPAS299, KG1, NAMALWA, or Daudi cells was estimated by Western blot analysis. (D) 1.0 × 105 of hematological cancer cell lines (Jurkat, K562, MOLM-13, NOMO-1, RPMI8226, Raji, or SKM-1) were cultured with 1G244 at doses of 0–10 µM for 72 h. Cell number was estimated by a colorimetric assay using WST-1 reagent (n = 6). (E) Expression level of HCK or CARD8 in Jurkat, K562, MOLM-13, NOMO-1, RPMI8226, Raji, or SKM-1 cells was estimated by Western blot analysis. (F) Knockdown studies of HCK in MM.1S cells. NT, no treatment; GFP, control vector; KD, knockdown. Expression level of HCK was estimated by Western blot analysis. (G) 1.0 × 105 of MM.1S cells and their transfectants were cultured with DPP8/9 inhibitors (1G244 or talabostat) at doses of 0–100 µM for 6 h. Cytotoxicity was estimated by a LDH release assay (n = 6).